1. Field of the Invention
The present invention relates to a fractionating apparatus for fractionating a liquid containing sample constituents onto a sample plate by dropping the liquid from a distal end of a probe.
2. Description of the Related Art
In the related art, when an effluent solution from a liquid chromatography is automatically dropped from a distal end of a probe onto a sample plate for MALDI-TOF (Matrix assisted laser desorption ionisation time of flight) or FT-IR (Fourier Transform Infrared Spectroscopy), the sample plate is moved closer to the effluent solution appearing from the distal end of the probe, because the amount of liquid droplet to be dropped is as small as about 1 μL, the sample plate is contacted with the liquid droplet, and the effluent solution is fractionated onto the sample plate.
In the related-art apparatus, using a method for fractionating the liquid by moving the sample plate closer to the liquid droplet, the sample plate and the liquid droplet are contacted at one point to fractionate the liquid successfully, but the liquid droplet and the sample plate are not contacted or a distal end of the probe contacts the sample plate at another point on the sample plate, resulting in a failure of hurting the surface of the sample plate, because the sample plate is not necessarily supported completely horizontally. In the MALDI-TOF analysis, because an electric field is applied to the sample plate at the time of analysis, the spreading of electric field is not uniform, if the sample plate is hurt, causing the analysis precision to be worse.